The present invention relates to a vacuum-suction degassing apparatus, in which gas-forming solute ingredients are removed or recovered from a melt, such as a molten metal, matte, or slag, through a porous member.
Conventionally, the RH method, DH method, and other degassing methods are used to remove gas-forming solute ingredients from a molten metal. According to the RH or DH method, a large quantity of argon gas is blown into the melt, the surface of which is kept at a vacuum or at reduced pressure so that the partial pressure of the gas-forming ingredients is lowered, thereby removing these ingredients.
Requiring the use of argon gas in large quantity, however, the conventional RH or DH degassing method entails high running cost. Since much argon gas is blown into the melt, moreover, the melt is liable to splash so that many metal drops adhere to the wall surface or some other parts of the apparatus, which requires troublesome removal work. To cope with this splashing of the melt, furthermore, the apparatus is inevitably increased in size, resulting in higher equipment cost.